This research study was financially supported by ENI Group environmental Department. The Federal Department of Forestry, Port Harcourt, is thanked for having permitted to capture the specimens studied in this paper. Critical reviews of this manuscript were provided by Dr Dario Capizzi, Dr Ernesto Filippi, Dr Zena Tooze, and Dr Massimo Capula. Prof. Rick Shine provided invaluable comments on the submitted draft version. We are indebted with the curators of the Zoological Museum of Copenhagen (Denmark) and of the California Academy of Sciences (San Francisco, USA) for having allowed examination of the specimens under their care. CC was funded by the Copenhagen Museum through European Community – Access to Research Infrastructure action of the Improving Human Potential Programme, COBICE, and by the California Academy of Sciences (CAS).